Preheat the oven to 180C/350F/Gas 4, and line a baking tray with parchment paper, or a silicone mat. Set aside.
Whisk together the flour, oats, baking powder, baking soda, and salt. Set aside.
Whisk together the coconut oil and sugar until combined. Add the egg, and vanilla, and mix until combined. Add the dry ingredients, and mix until just combined. Fold in the chocolate chips.
Roll the dough into 1.5oz balls, place on the prepared baking tray, and bake for 10 - 12 minutes. Allow to cool on the baking tray for 5 minutes before transferring to a wire rack to cool completely.
Notes
Cookies stay fresh covered at room temperature for up to 1 week. Cookie dough balls can be kept in the fridge for up to 5 days, or frozen for up to 3 months. Bake from frozen for an extra minute.